A new and highly stereocontrolled entry to terminal conjugated trienes is described which relies upon the diastereoselective [2,3]Wittig rearrangement of > (silyl)allylic propargyl ethers followed by Peterson olefination. The synthetic utility of this method is demonstrated by the stereocontrolled synthesis of sarohornene B and C (marine natural products).
This invention relates to novel N-derivatives of 1-deoxy nojirimycin, to the method for their preparation and to their use in the treatment of diabetes and the use against retro-viruses, particularly in the treatment of acquired immuno-deficiency syndrome (AIDS).
New N-alkyl, alkenyl and benzyl substituted DNJ derivatives incorporating a silicon atom in the substituent were synthesised. Kinetic parameters (K-i, t(1/2)) for inhibition of rat intestinal alpha-glucohydrolases as well as human lysosomal alpha-glucosidases were measured. New DNJ derivatives are potent and selective inhibitors of intestinal alpha-glucohydrolases. (C) 1997, Elsevier Science Ltd.
Hiemstra, Henk; Klaver, Wim J.; Speckamp, W. Nico, Recueil des Travaux Chimiques des Pays-Bas, 1986, vol. 105, p. 299 - 306
作者:Hiemstra, Henk、Klaver, Wim J.、Speckamp, W. Nico
DOI:——
日期:——
Rhodium Complex-Catalyzed Cycloisomerization of Allenenes: Exo and Endo Cyclization Depending on the Auxiliary Ligands
作者:Tatsuya Makino、Kenji Itoh
DOI:10.1021/jo035551x
日期:2004.1.1
having an exo-alkylidene moiety. In this cycloisomerization, (E)- and (Z)-allenenes are transformed stereospecifically to the corresponding cyclic (E)- and (Z)-1,4-dienes, respectively. On the other hand, the reactions under carbon monoxide atmosphere exclusively afford seven-membered-ring products through an endo-mode cyclization. The unusual cyclization involves an allylic C−H activation process. The